Machine clamp



Dec. l0, 1929. af P. GRAVES .MAcHiNE om? Filed March 31, 1926 3 Sheets-Sheet -1 Dec. l0, 1929. B, P, RAVE-s 1,738,647

. MACHINE CLAMP Filed March 3l. 1926 I 3 Sheets-Sheet 2 gif nm lm lm Devn 1o, 1929. BP,GRAVES 1,738,647

MACHINE CLAMP Filed March 31. 1926v 5 Sheets-Sheet 3 faim@ 61M.

Patented Dec. l0, 1929 BENJAMIN P. GRAVES, OF CRANSTON, Rit-ISDE ILAND, .ASSIGNOR T BROWN AND SEARPE MANUFACTURING COMIANY, 0F RQVIDENCE, RHODEVISLAND, A COR- PORATION OF RHODE ISLAND MACHINE CLAMP Application led March 31, 1926.

My invention relates to machines, particularly milling machines and includes a new type of split double clamping bearing for parallel arms.

I am aware that in milling machines, to

provide two or more points of support for the arbor yoke, a plurality of overhanging arms have been mounted in the column thereof. to form a supporting base line therefor. My invention relates to a milling machine provided with two or more overhanging arms and includes means whereby the overhanging arms may be adjustably clamped to the column and to the arbor yoke in a uniform plane thereby insuring that the overhanging arms will be parallel to each other throughout their length to form a perfect base line of a triangle to correspondingly evenly support the arbor yoke. Y

In milling machines it has been customary to provide a plurality of bearings, one relatively near the front end thereof, the-other relatively near the back tosupport the overhanging arm inthe column. My invention f specilically provides means whereby two overhanging arms may be simultaneously clamped in a uniform plane in each set of bearings both front and back in the column. I also provide means for adj usting the clamping relation between said bearings and clamping` device. l

To these ends I specifically provide a new type of split double bearing'having parallel bores therein for the overhanging arms to evenly and uniformly clamp simultaneously each overhanging arm. I employ in my preferred embodiment this general type of split double bearing in three places, namely at the front of the column, at the back of the column and in the arbor yoke.

These and such other objects of my invention as may. hereinafter appear will be' best understood from a description of embodiments thereof such as are shown in the accompanying drawings.

In the drawings, Fig. 1 is a side elevation of the column, overhanging arms, cutter arbor and cutter of a light duty milling machine.

Fig. 2 is a front elevation thereof.

Serial No. 38,7135.l

Fig. 3 is a cross sectional view taken alon the line 3-3 of Fig. l. v

Fig. 4 is a cross sectional view taken along the line 4-4 of Fig. l.

Fig. 5 is a cross sectional view Vtaken along the line 5-5 of Fig. l.

Fig. 6 Vis a side elevation of a portion of a side of the column showing the means I employ to individually adjustthe clamping action of each individual front. `and bac split bearing of the column. y

Fig. 7 is a side elevation similar' to Fig. l of a heavy duty'milling machine.

Fig. S isa cross sectional view taken along the lineS-S of Fig. 7. f l In the drawings, 10 generally represents the cutter arbor supporting column of aV milling machine having a plurality of. overhanging arms l2a and 1 2b adjustably mounted therein. The usual arbor yokel 14 is adjustably mounted on the front of said overhanging arms y12a and 12b and contains the usual centre 16 for mounting the cutter arbor 18 on which the usual cutting tool 20 is suitably mounted as usual, the opposite end of the cutter arborlS registering with the spindle in the column 10 as usual. 'Ihe desirability of having a plurality of overhanging arms to provide a base line on which the arbor yoke may be more firmly secured has already been pointed out. le As also intimated, in my preferred embod-` iment, I preferably employ a new type of .split double flexible bearing for supporting the-two overhanging arms l2a and 12b and I use this general type ofbearing at all the usual points of support of the overhanging arms, namely the iieXible double bearing 22 for the overhanging arms at the back of the column, the flexible double bearing 24 for the overhan ging arms at the front ofthe columnV and the flexible double bearing 26, for y the arbor yoke 14. Figs. 3, 4 and 5'are cross sectional views of these split double bearings 26, 24 and 22 respectively, which as eX- plained are generally similar in structure and function. l

The type of split double bearing shown in 8, which as explained isthe type used for both light and heavy duty machines on the arbor yoke 14, includes the two parallel bores 30a and 30b for receiving the front ends of the overhanging arms 12 and 12?. In my preferred embodiment, to provide a flexible bearing, the interior of the arbor yoke is centrally cored in a manner to be explained. Each of the walls of said parallel bores 30a and 30b is provided with a preferably vertical split 32a and 32" extending into the cored portion 34 underneath said bearings 31a and 31". The portion of the yoke 14 between said bearings 31a and 31b is also preferably cored as at 36 to provide flexibility. It is thus obvious that the vertical splits 32a and 32b extending` into the cored portion 34 provide each bore 30a and 30b with the relatively fixed outer sidesl 38a and 385 comprising. slightly more than half the periphery of said bores and provide the relatively flexible inner sides 40a and 40" for each bearing, comprising sliffhtlyless than half the periphery of said bores separated by said splits' 32.a and 32b from said rely atively fixed sides33a and 38h. Said sides 40a and 40b are rendered relatively flexible Vasthey extend between the splits V32?L and 32b and the central cored portion `36 between said bores *).a and 301% r v Ivprovide clamping means connecting ythe flexible portions ,40a and 40or of said'split dou- *bleA bearings to simultaneously draw said flexible portions of eachy bearing toward the other relatively'fixed portions37L and 33" of Y each bearing to simultaneously clamp each bearingv of a set to its respective overhanging arm. In the preferred embodiment shown in Fig. 3, said means is preferably constructed as follows. A bore 42 prefer'- ably of smaller diameter than said parallel bores p30?L andA 3(1)b is preferably provided in the base 44a of one of said individual bearings, 31a or 31", inmy preferred embodiment throughthe.base44a of the individual bears A ing 31a substantially at rightangles to said parallel bores 30a and '30b and through the vertical Split 32a in the bearing 31a. rlhe clamping bolt 46 is adapted to project through said bore 42. Said bolt 46 is provided with anl inner end 48- adapted-whenv in set position'to extend through the cored-portion 36 'between' said bearings 31a and 31b to the inner side of the base 44b ofthe inner flexible side b` of the bearing 31h. Said bolt is provided with' a threaded portion 49 adjacent to the sidevof said cored portion 36 near the base 44 and said bolt 46 is also'provided with the bolt-head 50 exterior of said bearing 26 and ,inner side 58' of the base 44a of the flexible in# ner side 40a of the bearing 31a. I also pro- 'S vide means to prevent said nut 52 from turn-v will move inward to abut the inner side of the base 441" of the flexible inner side 4Gb of the bearing 31b to force it outwardto firmly clamp the overhanging arm 12b in the bore 30b and that the base 56 of the nut 52 will abut the inner side of the base 44a of the flexible side 40a of the bearing 31a and through the medium of the threaded connection 4954 will draw the inner flexible side 40n of the vwill be unable to turn and that the bolt 46 bearing 31a outward to clamp the overhanging arm 12EL firmly within vthe bearing 31a.

It is thus obvious that as the bolt is turned thatV the flexible inner sides 4()A and 40b of said splitv flexible bearings 31a and 31b will be simultaneously dra-wn outwards to simultaneously cla-mp bothvo'verhanging arms 12 and 12h within the respective bearings 31 and 31h as shown in Fig. 3.k Although the Y `end '48 of the bolt 46 may directly abut the inner sideof base 44b of the flexible side 40?,

the plug 57 may be seated in the b-ore 59 ini said base 44h, the end 48 ofthe bolt 46then abutting the base 61 of said plug.

In Figs. 1-6 I show my invention applied Y vto a light duty milling machine, 4whereas in Figs. 7j and .8 I show the preferred type of my invention employed on va heavy duty milling machine'. In the heavy duty milling machine shown in Figs. .7 and 8 the flexible double bearings 22 and 24 forthe front and back of the column respectively are identical in construction with'the split double bearing i 26 which has-just been described for use on the arbor yoke 14 in either type. The column. underneath the split double bearing, however, is normally hollow and the cored por-v tion underneath the bearing normally in" cludes the ventire hollow body 34 of the column. The split double bearing 24 for the front of the column as shown in Fig; 7 and Fig. 8 in section is identical in construction to the split double bearing 26 hitherto described for use in thearbor yoke 14, the

split double bearing 22 for use onthe back of the column is also videntical in construction to the split double bearing 26 for yuse on the yoke 14, with the exception that the iin 62 projects in a rearwarddirection to abut the inner rear side 70 of the back wall of the column.

In the preferred embodiment for use on a liglitfduty milling machine asshown in Figs.

1-6, I provide in additions manually open ated device for simultaneously'operating the clamping means of both sets of flexible bearings so that the overhanging arms l2a and 12b may be simultaneously clamped in their flexible double bearings 24 and 22 located respectively at the front and back of the column.

In my preferred embodiment shown and as illustrated in detail in Figs. 4 and 5, Fig. 4

being a cross sectional view of the bearing 24 and Fig. 5 being a cross sectional view of the bearing 22, I provide in the bearing 24 the portion of the end of the bolt 46 located centrally of the cored portion 36 with the preferably integral gear 72 andI provide in similar position a gear 74 on the rear bearing 22 and I mount on said column l0 so as to have .the teeth thereof register within the gear teeth of said respective gears 72 and 74, the transversely extending rack 7 6 provided with the aforesaid teeth 7 8 on the lower edge against the fixed sides 38a and 38h of said bearing 24 and itis also obvious that as the bolt 46 is revolved forward it will tend to draw the rack 76 forward which in turn will tend to revolve the bolt 46 of the rear split bearing 22 to simultaneously draw the flexible sides 40"L and 40'b of said bearing outward to clamp said overhanging arms l2f1and 12D firmly against the fixed sides 38 and 38D thereof to firmly secure said arms at the rear of the column 10. It isthus obvious that I have provided a device which will simultaneously clamp the overhanging arms in each respective bearing 24 and 22 thereof at the front and rear thereof. i Y

In the preferred embodiment shown in Figs. 4 and 5, I also provide means for adjusting the clamping relation between the clamping means for the front bearing 24 and the clamping means for the rear bearing 22.

To accomplish this, in my preferred embodiment, I provide the additional bore 82 in the base 44b of the bearing 31h approximately in line with and parallel with the bore 42 in the base 44"L of the bearing 31a. The inner end of said bore 82 up tothe split 32h is preferably threaded as at 84 for a purpose to be described. The outer end 86 of the bore in the fixed side 38b is of slightly larger diameter. I insert the bolt 88 through the portion 86 of the bore and screw the inner threaded portion 90 thereof' into the threaded portion S4 of said bore, the inner end 92 of said bolt thus projecting within the cored portion 36 between the bores of said individual bearings 31 and 31". The head 94 of said bolt is constructed as shown in detail in Fig. 6, the centre portion thereof being provided with the elongated slot 96 for receiving the end of a screw driver for turning'purposes and its outer periphery is provided with semi-circular grooves 98 arranged at equidistant intervals thereon. A screw socket 100 is provide-d in the side of the Cole umn l() adjacent to the outer periphery of the bolt head 94. It is thus obvious that the bolt head 94 may be turned to vary the projection of the inner end 92 within the cored portion 36 and that when set in desired position the head 94 of said bolt may be adiustably locked to said column l0 by inserting the screw 102 through the adjacent semi-circular groove 98 in the bolt head 94 and into the threaded socket `100. Although I have explained the details of this clamp adjusting device as applied to the rear bearing 22, as shown in Fig.

4 an identical construction is employed forI adjusting the front bearing 24. It is thus obvious that I have provided means for adj usting the 'clamping relation between the front and back bearings of the column.

Though I have shown the split bearings 22,

24 and 26 provided with vertical splits, it is' obvious that horizontal or angularly disposed splits may be employed provided however one portion of each bearing is relatively fixed and the opposite portion thereofrelatively flexible, but that in order to employ the iniproved type of clamping mea-nein Fig. 7, it is preferable th at vertical splits be employed. It is also obvious that the outer portions 38a and 38' of said bearings may be relatively flexible and the inner portions 40a and 40b of said bearings relatively fiXed without departing from the spirit of mvinvention.

As pointed out, my invention not'only resides in the specific type of split double beara ing shown and described for use withv any type of a plurality of over-hanging arms in any machine,b'ut also comprises in a milling machine employing two overhanging arms for'supporting the cutter arbor the combination of means to clamp a separatefront col- YLIl() umn bearing forsaid arms and a separate rear column bearing for said arms in a uniform plane to keep said arms in parallel align# j ment throughout their length andalso to clamp the Varbor yoke to saidl overhanging varms in the Vsame uniform plane to keep them in parallel alignment throughout their length so that they may form a more perfect base for mounting the cutter arbor thereon. The essential feature of my invention therefore is,

that any type of flexible bearings preferably j constructed as shown and described to prevent dust, dirt, etc., from entering into the splits thereof may be employed provided with any suitable type of clamping means if the clamping-means thereof function in their clamping action in a uniform or a parallel plane.

It is `understoodthat my invention is not limited Vto the specific em'bodimentsshown and that various deviationsrmay be madethere-from without departing from the spirit-k vfiexible portion separated by said split from the other outer portiony and asimilar back set, clamping means connecting said portions to simultaneously draw the inner flexible portion of each bearing of each set substantiallyequal amounts toward thev other outer portion in a uniform planeto simultaneously clamp each bearing of a set to its respective overh'anging arnna manually operated device for simultaneously operating the clamping means of both sets of bearings, an arbor yoke adapted to support a cutter arbor detachably mounted on said arms VVcontaining parallel bearings for each arm extending transversely 'thereof in line with they bearings vin the column each having a vertical split and an inner' flexible portion separated by said split from the other outer portion thereof and clamping means connecting saidlportions to simultaneously drawthe-inner flexible portion of each bearing substantiallyv equal amounts to its overhanging 'arm in a plane uniform with the plane of the clampingiaction of .the column bearings. Y Y f Y 2. In a milling machine, a column, two overhangingarms, Vbearings for said overhanging arms: extending transversely of said column in the same horizontal plane to form a base linefor the cutter comprising, a front set'of'bearings each havinga split and a flexible portion separated by said split from the other portionA and a` similar back set, clamping-means connecting said portions to simultaneously draw the flexible portion of each bearingy of each set substantially equal l amounts toward the otherl portion in a uniform plane to simultaneously clamp each bearing of a set to its respective over-hanging arm, an arbor yoke adapted to support a cutter arbor detachably mounted on 'said arms containing bearings for each arm extending transversely thereof inline with the bearings in the'column each having a split and a flexible portion separated by said' split from the other portion thereof and clamping means Y eonnecting'said portions to simultaneously draw thevflexible portion of eachbearing substantially equal amounts toward the other portion to simultaneously clamp each bearing tof-its overhanging arm in a plane uniform vwith the plane of the clamping action of the column bearings.

3.. In a milling machine, a column, two overhanging arms, bearlngs for said overhanging; arms extending transversely of said column inthe same horizontal plane to. form abase line for the cutter comprising,rv a. front' set of bearings each having asplit and a fiexible portion separated by said split fromv the other portion and a similar back set, clamping meansk connecting Vsaid portionsto simultaneously draw the exible portion of each bearing of each set substantially equal amounts toward the other portion in a uniform plane to simultaneously clampV each bearing of a setto its respective overhanging arm, a manually operated device for simultaneously operatingthe clamping means of lboth sets of bearings and means for adjusting theclamp-ing relation between said clamping means. i A 4. In a machine having two parallel adjustable arms, the combination of a'double bearing for said arms comprising twok flexible bearings having parallel bores each having a vertical split near the base thereof, a relatively fixed outer side, and a relatively flexible inner side sepa-rated by said split from said relatively fixed side,said bearings being separated from eachl other by. an open portion: torender the inner sides of said bearings fiexible, a bore extendingthrough the. base of one,l of said bearings substantially atV right angles to said parallelbores, a clamping bolt projecting through said bore having an inner end extending through said` open portion to abut the inner end ofthe flexible side ofsaid'opposite bearing and having ay threaded portion adjacent the opposite side of said open portionand a bolt head projectingexterior of said bearing, a nut threaded onV said threaded yportionofsaid bolt containing bearing having its base abutting the inner side of the inner flexible side of said bolt containing bearing and means to prevent said nutfrom turning on turning of said-bolt. In testimony whereof I affix my signature.

BENJAMIN P. GRAVES. Y 

